I have read of using a little stop bath to clean a tray or bottle used for developer. But of course thorough rinsing is needed after that. As for bottles used for stop bath and fixer, I would just use several rinses with water. I have never heard of using fixer to clean a bottle that held stop bath. If your bottles are each planned to contain the same or similar chemicals, several thorough rinses should be adequate.(posted 8931 days ago)